Fuel cartridge with connecting valve

ABSTRACT

A shut-off valve or connecting valve capable of connecting a fuel supply to a fuel cell is disclosed. The valve comprises a first valve component and a second valve component. Each valve component has an outer housing and a biased slidable member disposed inside the housing forming an internal seal. During the connection process, the two valve components establish an inter-component seal. Afterward, in one suitable embodiment the slidable member moves inward and opens the internal seal in the valve component to establish a flow path. In another embodiment, the slidable member moves inward and exposes a first filler and the first filler abuts a second filler in the other valve component to establish a flow path. In other embodiments, at least one valve component is sized and dimensioned to limit access to the internal seal.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of U.S.application Ser. No. 13/238,898, filed on Sep. 21, 2011, now U.S. Pat.No. 8,851,114, which is a divisional of U.S. patent application Ser. No.12/431,352, filed on Apr. 28, 2009 and issued as U.S. Pat. No. 8,047,229on Nov. 1, 2011, which is a divisional of U.S. patent application Ser.No. 10/629,006, filed on Jul. 29, 2003, and issued as U.S. Pat. No.7,537,024 on May 26, 2009. The '898, '352, and '006 applications areincorporated by reference herein in their entireties.

FIELD OF THE INVENTION

This invention generally relates to fuel cartridges for fuel cells, andmore particularly this invention relates to disposable and refillablefuel cartridges. This invention also relates to a valve connecting afuel cartridge to a fuel cell or to a refilling device.

BACKGROUND OF THE INVENTION

Fuel cells are devices that directly convert chemical energy ofreactants, i.e., fuel and oxidant, into direct current (DC) electricity.For an increasing number of applications, fuel cells are more efficientthan conventional power generation, such as combustion of fossil fueland more efficient than portable power storage, such as lithium-ionbatteries.

In general, fuel cell technologies include a variety of different fuelcells, such as alkali fuel cells, polymer electrolyte fuel cells,phosphoric acid fuel cells, molten carbonate fuel cells, solid oxidefuel cells and enzyme fuel cells. Today's more important fuel cells canbe divided into three general categories, namely fuel cells utilizingcompressed hydrogen (H₂) as fuel, proton exchange membrane (PEM) fuelcells that use methanol (CH₃OH), sodium borohydride (NaBH₄),hydrocarbons (such as butane) or other fuels reformed into hydrogenfuel, and PEM fuel cells that use methanol (CH₃OH) fuel directly(“direct methanol fuel cells” or DMFC). Compressed hydrogen is generallykept under high pressure, and is therefore difficult to handle.Furthermore, large storage tanks are typically required, and cannot bemade sufficiently small for consumer electronic devices. Conventionalreformat fuel cells require reformers and other vaporization andauxiliary systems to convert fuels to hydrogen to react with oxidant inthe fuel cell. Recent advances make reformer or reformat fuel cellspromising for consumer electronic devices. DMFC, where methanol isreacted directly with oxidant in the fuel cell, is the simplest andpotentially smallest fuel cell, and also has promising power applicationfor consumer electronic devices.

DMFC for relatively larger applications typically comprises a fan orcompressor to supply an oxidant, typically air or oxygen, to the cathodeelectrode, a pump to supply a water/methanol mixture to the anodeelectrode and a membrane electrode assembly (MEA). The MEA typicallyincludes a cathode, a PEM and an anode. During operation, thewater/methanol liquid fuel mixture is supplied directly to the anode,and the oxidant is supplied to the cathode. The chemical-electricalreaction at each electrode and the overall reaction for a directmethanol fuel cell are described as follows:

Reaction at the anode:CH₃OH+H₂O→CO₂+6H⁺+6e ⁻

Reaction at the cathode:O₂+4H⁺+4e ⁻→2H₂O

The overall fuel cell reaction:CH₃OH+1.5O₂→CO₂+2H₂O

Due to the migration of the hydrogen ions (H⁺) through the PEM from theanode through the cathode and due to the inability of the free electrons(e⁻) to pass through the PEM, the electrons must flow through anexternal circuit, which produces an electrical current through theexternal circuit. The external circuit may be any useful consumerelectronic devices, such as mobile or cell phones, calculators, personaldigital assistants and laptop computers, among others. DMFC is discussedin U.S. Pat. Nos. 5,992,008 and 5,945,231, which are incorporated byreference in their entireties. Generally, the PEM is made from apolymer, such as Nafion® available from DuPont, which is aperfluorinated material having a thickness in the range of about 0.05 mmto about 0.50 mm, or other suitable membranes. The anode is typicallymade from a Teflonized carbon paper support with a thin layer ofcatalyst, such as platinum-ruthenium, deposited thereon. The cathode istypically a gas diffusion electrode in which platinum particles arebonded to one side of the membrane.

The cell reaction for a sodium borohydride reformer fuel cell is asfollows:NaBH₄(aqueous)+H₂O→(heat or catalyst)→(H₂)+(NaBO₂)(aqueous)H₂→2H⁺+2e ⁻(at the anode)2(2H⁺+2e ⁻)+O₂→2H₂O(at the cathode)

Suitable catalysts include platinum and ruthenium, among other metals.The hydrogen fuel produced from reforming sodium borohydride is reactedin the fuel cell with an oxidant, such as O₂, to create electricity (ora flow of electrons) and water byproduct. Sodium borate (NaBO₂)byproduct is also produced by the reforming process. Sodium borohydridefuel cell is discussed in U.S. published patent application No.2003/0082427, which is incorporated herein by reference.

One of the most important features for fuel cell application is fuelstorage. Another important feature is to regulate the transport of fuelout of the fuel cartridge to the MEA. To be commercially useful, fuelcells such as DMFC systems should have the capability of storingsufficient fuel to satisfy the consumers' normal usage. For example, formobile or cell phones, for notebook computers, and for personal digitalassistants (PDAs), fuel cells need to power these devices for at leastas long as the current batteries, and preferably much longer.Additionally, the fuel cells should have easily replaceable orrefillable fuel tanks to minimize or obviate the need for lengthyrecharges required by today's rechargeable batteries.

However, a need exists for a connecting valve that connects anddisconnects the fuel cartridge to the fuel cell and the refilling fuelcontainer.

SUMMARY OF THE INVENTION

Hence, the present invention is directed to a fuel supply adapted foruse with a fuel cell.

The present invention is also directed to a fuel supply adapted for usewith a direct methanol fuel cell.

The present invention is also directed to a fuel supply adapted for usewith a reformat fuel cell.

The present invention is also directed to a fuel supply having a valvecapable of connecting the fuel supply to a fuel cell. Fuel supply can bea fuel cartridge, a fuel container, or a fuel line, among other fuelsupplies, and fuel cell includes an optional pump. The connecting valvecan be used in the transport of fuel from the fuel supply to the fuelcell and it can also be used in the transport of byproducts from thefuel cell back to the fuel supply or a waste container. A fuel supplycan have multiple connecting valves.

One aspect of the present invention is directed to a valve comprisingtwo valve components capable of connecting a fuel supply to a fuel cell.Each valve component has a housing and a biased slidable inner body,which cooperates with a sealing member to form an internal seal in eachvalve component. During the connection the two valve components form aninter-component seal at least before the internal seals open to create afluid flow path through the valve.

One valve component is connected to the fuel supply and the other valvecomponent is connected to the fuel cell. The slidable inner body can bea sphere or a valve head with a body member or the like. The slidableinner body may have a pushrod, which makes contact with the opposingslidable inner body. The slidable body is biased by a spring member,which can be a helical spring, a wave spring, compressed foam, anelastomeric or rubber spring, or the like. The spring constants can besubstantially the same in both valve components or they can besubstantially different. In one example, the spring constant of thespring in the valve component connected to the fuel cell is lower thanthe spring constant of the spring in the valve component connected tothe fuel supply, so that the internal seal in the valve componentconnected to the fuel cell opens first.

The sealing member can be an o-ring, a sealing face, a washer, anelastomeric ball or the like. The inter-component seal can be formedbetween any portions of the opposing valve components. For example, itcan be formed between a portion of the housing of one valve componentand the sealing member of the other valve component or between thehousing of one valve component and the housing of the other valvecomponent. The inter-component seal can be formed before any internalseal opens, or after the internal seal of the valve component connectedto the fuel cell opens.

The fluid flow path can be established in the space between the housingand the slidable inner body, or in one or more channels defined on oneor both of the slidable inner bodies. The valve may also have a liquidretention material surrounding the first and second valve components, orwithin one or both valve components where the liquid retention materialis located in the downstream direction from the internal seal of thevalve component. The valve may further have a retainer to keep the twovalve components in the connected position.

One or both of the internal seals can be opened by a pump, or the pumpwhen in the off position can provide the internal seal to the valvecomponent. One or both of the valve components may have a secondinternal seal, which can be a closed washer or a duckbill valve. Theduckbill valve can be sized and dimensioned to limit access to theinternal seal. At least one of the valve components may have a nozzle ora sleeve sized and dimensioned to limit access to the internal seal.

Another aspect of the present invention is directed to another valvecomprising two valve components capable of connecting a fuel supply to afuel cell. The first valve component comprises an outer housing, abiased sleeve slidable relative to the outer housing, and a fillermaterial contained within the biased sleeve. The second valve componentcomprises an outer housing, a sleeve and a filler material containedwithin the sleeve. During connection, the first sleeve and the secondsleeve push each other so that the filler materials abut each other toform a fluid flow path through the valve. The sleeve in the second valvecomponent can be fixed relative to the housing or be slidable relativeto the housing.

With respect to this valve, during connection the two valve componentsform an inter-component seal between them, preferably before the fuelflow path is formed. The slidable sleeve is biased by a spring member,which can be a helical spring, a wave spring, compressed foam, anelastomeric or rubber spring, or the like. During connection the firstsleeve is pushed back to expose at least a portion of the fillermaterial. The filler material in the sleeve can be positioned behind theleading edge of the sleeve to form a cavity, and the exposed portion ofthe filler material in the first sleeve is sized and dimensioned to bereceived in this cavity.

This valve may further comprise a liquid retention material positionedspaced apart from the fluid flow path. The fuel retention material maybe a liquid swellable material and may have additive(s) containedtherein. The liquid retention material can be disposed in the annulararea between the outer housing and the sleeve in the valve component.This valve can also have a nozzle or an outer collar, sized anddimensioned to limit access to the valve component.

In accordance with another aspect of the present invention, the valvealso has a liquid retaining material, disposed in at least one valvecomponent, capable of retaining fuel or other liquids remaining in thevalve when one valve component disconnects from the other valvecomponent. The liquid retention material is located in the downstreamdirection from the internal seal of the valve component.

In accordance with another aspect of the invention, the first valvecomponent has a housing and an internal seal formed by a slidable innerbody biased against a sealing member and the second valve component mayhave a duckbill valve. During connection, the housing enters theduckbill valve to open the internal seal of the duckbill valve, and forman inter-component seal at least before the internal seals open tocreate a fluid flow path through the valve. A pump can be used to openthe internal seal in the first valve component. The duckbill valvecomprises wipers that form at least one chamber with the outer surfaceof the housing of the first valve component, where pressurized fuel, ifany, can expand in the chamber and bleeds off its pressure when thevalve is disconnected. The duckbill valve may comprise a liquidretention material to absorb fuel or an additive capable of mixing withthe fuel. The second valve component may also have a second internalseal.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, which form a part of the specification andare to be read in conjunction therewith and in which like referencenumerals are used to indicate like parts in the various views:

FIG. 1( a) is a cross-sectional view of two unconnected valve componentsof an embodiment of the present invention; FIG. 1( b) is across-sectional view of the two valve components of FIG. 1( a) incontact with each other; and FIG. 1( c) is a cross-sectional view of thetwo valve components of FIGS. 1( a) and 1(b) connected to each other toallow fuel to flow from a cartridge to a fuel cell;

FIG. 2( a) is a cross-sectional view of an alternative valve componentof FIGS. 1( a)-(c); FIGS. 2( b) and 2(c) are cross-sectional views ofother alternative valve components;

FIGS. 3( a) and (b) are schematics of the valve components of FIGS. 1(a)-(c) showing alternative flow paths with certain details omitted forclarity; FIG. 3( c) shows an alternative valve component of FIG. 3( a)and FIG. 3( d) shows an alternative flow path through the valvecomponents;

FIG. 4( a) shows cross-sectional views along lines 4 a-4 a in FIG. 3( a)and FIG. 4( b) shows cross-sectional views along line 4 b-4 b in FIG. 3(d);

FIG. 5 shows cross-sectional views of suitable O-rings;

FIG. 6 is a cross-sectional view of another valve embodiment of thepresent invention;

FIG. 7( a) is a cross-sectional view of two valve components of anotherembodiment of the present invention with an inter-component sealestablished between the two valve components; FIG. 7( b) is across-sectional view of the two valve components of FIG. 7( a) with theinternal seal in one of the valve components opens; and FIG. 7( c) is across-sectional view of the two valve components of FIGS. 7( a) and 7(b)with both internal seals open;

FIG. 8( a) is a cross-sectional view of two unconnected components ofanother embodiment of the present invention; and FIG. 8( b) is across-sectional view of the two components of FIG. 8( a) connected toeach other to allow fuel to flow from the cartridge to the fuel cell;and

FIG. 9( a) is a cross-sectional view of two unconnected components ofanother embodiment of the present invention; and FIG. 9( b) is across-sectional view of the two components of FIG. 9( a) connectedtogether;

FIG. 10 shows cross-sectional views of suitable seals in FIGS. 9( a) and9(b);

FIG. 11( a) is a cross-sectional view of two unconnected components ofanother embodiment of the present invention; FIG. 11( b) is across-sectional view of the two components of FIG. 11( a) connectedtogether; and FIG. 11( c) is an alternative embodiment of FIG. 11( a);

FIG. 12( a) is a cross-sectional view of another valve component inaccordance to the present invention; FIG. 12( b) is a cross-sectionalview of the valve component of FIG. 12( a) being connected to acorresponding valve component; and FIG. 12( c) is alternative embodimentof FIG. 12( b);

FIG. 13 is a cross-sectional view of another valve component inaccordance to the present invention;

FIG. 14 is a cross-sectional view of another valve component inaccordance to the present invention; and

FIG. 15 shows cross-sectional views of alternate rubber springs.

DETAILED DESCRIPTION OF THE EMBODIMENTS

As illustrated in the accompanying drawings and discussed in detailbelow, the present invention is directed to a fuel supply, which storesfuel cell fuels such as methanol and water, methanol/water mixture,methanol/water mixtures of varying concentrations or pure methanol.Methanol is usable in many types of fuel cells, e.g., DMFC, enzyme fuelcell, reformat fuel cell, among others. The fuel supply may containother types of fuel cell fuels, such as ethanol or alcohols, chemicalsthat can be reformatted into hydrogen, or other chemicals that mayimprove the performance or efficiency of fuel cells. Fuels also includeaqueous potassium hydroxide (KOH) electrolyte, which is usable withmetal fuel cells or alkali fuel cells, and can be stored in fuelsupplies. For metal fuel cells, fuel is in the form of fluid borne zincparticles immersed in a KOH electrolytic reaction solution, and theanodes within the cell cavities are particulate anodes formed of thezinc particles. KOH fuel is disclosed in U.S. published patentapplication No. 2003/0077493, entitled “Method of Using Fuel Cell SystemConfigured to Provide Power to One or more Loads,” published on Apr. 24,2003, which is incorporated herein by reference in its entirety. Fuelsalso include a mixture of methanol, hydrogen peroxide and sulfuric acid,which flows past a catalyst formed on silicon chips to create a fuelcell reaction. Fuels also include aqueous sodium borohydride (NaBH₄) andwater, discussed above. Fuels further include hydrocarbon fuels, whichinclude, but are not limited to, butane, kerosene, alcohol and naturalgas, disclosed in U.S. published patent application No. 2003/0096150,entitled “Liquid Hereto-Interface Fuel Cell Device,” published on May22, 2003, which is incorporated herein by reference in its entirety.Fuels also include liquid oxidants that react with fuels. The presentinvention is, therefore, not limited to any type of fuels, electrolyticsolutions, oxidant solutions, or liquids contained in the fuel supply.The term “fuel” as used herein includes all fuels that can be reacted inany fuel cells, and includes, but is not limited to, all of the abovesuitable fuels, electrolytic solutions, oxidant solutions, liquids,and/or chemicals and mixtures thereof.

Also, as used herein “fuel supply” includes fuel cartridges, fuelcontainers and fuel lines, among other fuel supplies. The exemplaryembodiments of the present invention are described herein beingconnectable to a fuel cartridge. It is understood, however, that thepresent invention is suitable for use with any fuel supply, as definedabove. Furthermore, as used herein “fuel cell” includes an optionalpump, which may reside within the electrical component that the fuelcell powers. The pump is also attachable to the fuel supply.

Furthermore, the shut-off valves or connecting valves discussed hereinare suitable for communicating fuel from a fuel supply to a fuel celland for communicating liquid and/or gas byproducts produced in the fuelcell back to the fuel supply or to a waste container. While the presentinvention is described in detail below with respect to communicatingfuel from the fuel supply to the fuel cell, it is understood that thevalves of the present invention are suitable for transporting fluids,i.e., liquid or gas, to and from the fuel supply, and/or to and from thefuel cell.

In accordance with an embodiment of the present invention, shut-offvalve or connecting valve 10 comprises at least first valve component 12and second valve component 14, as shown in FIG. 1( a). First valvecomponent 12 or second valve component 14 can be mated either to fuelcartridge 16 or to fuel cell 18. Fuel cell cartridges and fuel cells aredisclosed in commonly owned, co-pending patent application Ser. No.10/356,793, entitled, “Fuel Cartridge for Fuel Cells,” filed on Jan. 31,2003. The '793 patent application is incorporated herein by reference inits entirety.

In this configuration, first valve component 12 comprises similarelements as second valve component 14. First valve component 12comprises housing 20, which encases sliding body 22 and o-ring 24.Sliding body 22 forms an internal seal with o-ring 24 to prevent fuelfrom being transported through first valve component 12 when the valvecomponent is not connected. Spring 30 pressed against stop 28 biasesbody 22, and body 22 is movable against spring 30. Housing 20 may alsohave retainer 29 to retain body 22 within the housing. Similarly, secondvalve component 14 comprises housing 32, sliding body 34 and o-ring 36.Spring 40 presses against stop 38 and biases sliding body 34. Slidingbody 34 forms an internal seal with o-ring 36 to prevent fuel from beingtransported through the valve component when unconnected. Sliding body34 is movable against spring 40. Housing 32 and sliding body 34 may alsohave retaining members 39 and 41, respectively, to retain sliding body34 within the housing. Also, as shown in FIGS. 1( a)-1(c), o-rings 24and 36 are shown to reside in grooves defined on housing 20 and 32,respectively. Alternatively, these o-rings can reside in grooves definedon sliding bodies 22 and 34.

To connect the fuel cartridge to the fuel cell and to transport fuelfrom the fuel cartridge to the fuel cell, first member 12 is insertedinto second member 14, as shown in FIGS. 1( b) and 1(c). Pushrod 42 onsliding body 22 contacts and acts on pushrod 44 on sliding body 34, asthe two valve components are brought into contact with each other. Aspushrods 42 and 44 push each other, springs 30 and 40 are partiallycompressed by sliding bodies 22 and 34. Springs 30 and 40 may have thesame resistance or spring constant, so that the internal seals in thevalve components are opened at the same time. Alternatively, springs 30and 40 can have different spring constants so that one internal seal isselectively opened before the other one. As shown in FIG. 1( b), spring30 has a lower spring constant so that the seal in first valve component12 selectively opens first. Preferably, before the internal seal infirst valve component 12 opens, body 20 of first valve component 12forms an inter-component seal with o-ring 36 of second valve component14. As first and second valve components 12 and 14 are being pushedfarther toward each other, body 22 comes into contact with stop 28 andstops, as shown in FIG. 1( c), or spring 30 is fully compressed and body22 stops, thereby causing body 34 of second valve component 14 to moveaway from o-ring 36. Channels 46, defined on the leading edge of housing20, move behind o-ring 36 and open up a flow channel from the fuelcartridge to the fuel cell, as shown by the flow line in FIG. 1( c).Depending on the spring constant of spring 30, channels 46 may movebehind o-ring 36 without having body 22 come to a stop. The flow linewould be in the opposite direction, if second valve component 14 weremated to the fuel cartridge. A lead-in chamfer can be provided onhousing 32 to protect o-ring 36 from potential damage caused by theinsertion of valve component 12 into valve component 14.

Alternatively, spring 40 may have a lower spring constant so that theseal in second valve component 14 opens before the seal in first valvecomponent 12 opens. In accordance to one aspect of the presentinvention, the spring positioned within the electronic device or fuelcell is the weaker spring, so that the valve component connected to theelectronic device or fuel cell is selectively opened first.

First and second valve components 12 and 14 may have otherinterchangeable configurations, such as those shown in FIGS. 2( a), 2(b)and 2(c). The valve component shown in FIG. 2( a) comprises a housing 48encasing ball 50, which is adapted to slide within housing 48 and o-ring52. Ball 50 is biased against o-ring 52 by spring 30 or 40. An internalseal is formed between ball 50 and o-ring 52, and housing 48 definesaperture 54, which is sized and dimensioned to receive pushrod 42 or 44.Pushrod 42 or 44 contacts and pushes ball 50 rearward to open theinternal seal. The valve component shown in FIG. 2( b) comprises housing48 encasing sliding body 56, which has sealing face 58 adapted to forman internal seal with lip 60 of housing 48. The valve component shown inFIG. 2( c) is similar to that in FIG. 2( a), except that o-ring 52 isinterchanged with sealing member 59. Sealing member 59 is preferably ano-ring having a triangular cross-section with three surfaces. Two of thesurfaces are pressed flush against lip 60 and the third surface forms aseal with ball 50, as shown. Ball 50 is preferably made from anelastomeric rubber, metal or metal coated with an elastomeric rubber.The sealing members and the o-rings can be made from the same material,such as elastomeric rubbers including Buna N Nitrile, other nitrilerubbers, ethylene propylene diene methylene terpolymer (EPDM) rubber orVitron® fluoro-elastomer, depending on the fuel stored in the fuelsupply.

To open the seal, pushrod 42 or 44 enters aperture 54 and pushes body 56or ball 50 backward against the biasing force of spring 30 or 40. Theoperation or sequence of establishing a flow path within valvecomponents 12 or 14 shown in FIGS. 2( a), 2(b) and 2(c) is similar tothe operation discussed in connection with FIGS. 1( a)-1(c) above, i.e.,an inter-component seal between the two valve components is establishedbefore the internal seals open.

FIGS. 3( a) and 3(b) show an alternative fuel flow path from the fuelcartridge to the fuel cell. Sliding body 22 defines one or more channels62 and sliding body 34 defines one or more channels 64. When the twovalve components are unconnected, the proximal ends of channels 62 and64 terminate at or before o-rings 24 and 36, respectively. The distalends of these channels terminate at pushrods 42 and 44, respectively,and the distal ends are positioned directly opposite to each other. Whenthe pushrods contact each other, channels 62 and 64 are in fluidcommunication with each other. However, fuel flow can only be initiatedafter the proximal ends of channels 62 and 64 are pushed past theo-rings. The flow line in FIG. 3( b) illustrates the fuel flow path.Again, the fuel flow line can be reversed depending on which valvecomponent is mated to the fuel cartridge.

FIG. 3( c) illustrates an alternative flow path, wherein channels 62 and64 are positioned in front of the o-rings before the two valvecomponents are connected. After the valve components are connected, thefuel flow path is the same as that depicted in FIG. 3( b). FIG. 3( d)illustrates that channels 62 and 64 may have a channel in thelongitudinal direction and a channel in the transverse direction. Thesechannels can be readily machined into the sliding bodies during themanufacturing process, or can be molded or die cast.

FIGS. 4( a) and 4(b) illustrate the shapes and locations that channels62 and 64 may have. These channels can be located on the surface ofpushrods 42 and 44 or inside of the pushrods. Any number of channels canbe located in the pushrods or in the sliding bodies.

FIG. 5 depicts the possible cross-sections of the o-rings describedherein to include triangular, square, circular, oval or polygonal shape.

FIG. 6 shows that any embodiment of valve component 12 or 14 shownherein is usable with any other embodiment. As shown, the valvecomponent illustrated in FIG. 2( b) is used opposite to the valvecomponent illustrated in FIG. 3( c). Pushrod 42 or 44 is sized anddimensioned to be received in aperture 54. Before the internal sealsinside the valve components, i.e., between sliding body 22 or 34 ando-ring 24 or 36 or between sealing face 58 and lip 60, are opened,second sealing face 66 of one valve component establishes aninter-component seal with the outer surface of lip 60 of the other valvecomponent. As pushrod 42 or 44 contacts and pushes sealing member 58rearward, it opens the internal seals within the valve components toopen the fuel flow path.

FIGS. 7( a)-7(c) show another embodiment of the present invention,showing in more detail a particular sequence of the inter-component sealbeing established and the internal seals being sequentially opened. InFIG. 7( a), valve component 12 has sliding body 22 biased by spring 30,which in this embodiment is an elastomeric spring and is discussedfurther below. O-ring 24 is fixedly disposed on sliding body 22 andforms an internal seal with a slanted inner surface on lip 60 of housing20. In this embodiment, housing 20 further has sleeve 68 formed on thefront of valve component 12. Valve component 14 is similarly constructedto valve component 12, as discussed above, except that it has a secondo-ring 70 fixedly disposed on the outer surface of housing 32. O-ring 70and the inner surface of sleeve 68 form the inter-component seal betweenthe valve components, as shown in FIG. 7( a). As used herein, the term“rubber” includes both rubber and elastomeric material and “elastomeric”includes both elastomeric material and rubber.

In FIG. 7( b), the two valve components are pushed farther toward eachother. Since spring 40 has a lower spring constant than spring 30, asdepicted by the relative thickness of the rubber springs, spring 40 iscompressed first and sliding body 34 is pushed backward, thereby openingthe internal seal in valve component 14 between o-ring 36 and lip 60. InFIG. 7( c), the two valve components are pushed farther toward eachother until housings 20 and 32 contact each other. At this junction, theinternal seal in valve component 12 between o-ring 24 and lip 60 isopened to create a fuel flow path through valve 10.

FIGS. 8( a) and 8(b) show another embodiment of the present inventionwhere fuel permeable filler is used to establish a flow path inconnecting valve 80. Preferably, the fuel permeable filler is capable oftransporting by capillary action fuel from inside the fuel cartridge,through connecting valve 80 and to the fuel cell. Such fuel permeablefiller is disclosed in the commonly owned, co-pending '793 patentapplication, which has already been incorporated herein by reference inits entirety.

Connecting valve 80 comprises first valve component 82 and second valvecomponent 84. First valve component 82 or second valve component 84 canbe mated to cartridge 16 or to fuel cell 18. In this configuration,first valve component 82 comprises outer housing 86, sleeve 88 andfiller material 90. Sleeve 88 is slidable in the longitudinal directionrelative to outer housing 86 and to filler material 90, and is biased byspring 92 against stop 94. Sleeve 88 may also have optional upstandingretaining wall 96, which cooperates with o-ring 98 disposed in theannular space between outer housing 86 and sleeve 88, to retain sleeve88 within first valve component 82. Preferably, sleeve 88 or 102 can beretained in the valve component by cooperating stops, such as stops 97and 99. O-ring 98 also provides a seal in this annular space. Secondvalve component 84 comprises outer housing 100, sleeve 102 and fillermaterial 104. Sleeve 102 may be slidable with respect to outer housing100 and filler material 104, and is biased by spring 106, as shown in.FIG. 8( a). However, sleeve 102 may be stationary or fixed so that it isnot movable relative to outer housing 102 and filler material 104.Preferably, the leading edge of filler material 104 is spaced behind theleading edge of sleeve 102, as shown in FIG. 8( a). This creates acavity 108, which is adapted to receive a portion of filler material 90from first valve component 82.

When the two valve components 82 and 84 approach each other forconnection, sleeves 88 and 102 contact each other first. Their leadingsealing faces 110 can form an inter-component seal. In a preferredembodiment, sleeve 102 is non-slidable and, therefore, sleeve 88 ispushed backward against spring 92. As sleeve 88 retreats, a portion offiller material 90 is exposed and received by cavity 108. When fillermaterials 90 and 104 contact and abut each other, a flow path throughthe filler materials is established to transport fuel from the cartridgeto the fuel cell, as shown in FIG. 8( b). Optionally, outer housings 86and 100 also possess leading sealing faces to form a secondinter-component seal.

Additionally, valve components 82 and 84 remain connected to each otherby at least one snap-on retainer such as the one shown in FIGS. 8( a)and 8(b). The snap-on retainer comprises a spring-loaded arm 112, whichis connected to one of the valve components and has head 114 at itsdistal end. Head 114 is sized and dimensioned to be received incorresponding cavity 116 located on the outer surface of the other valvecomponent. When head 114 snaps into cavity 116, the two valve componentsare retained in the connected position. Valve 80 may have a plurality ofsuch snap-on retainers. Furthermore, this snap-on retainer is alsousable with connecting valve 10 described above with respect to FIGS.1-7. Arm 112 can be spring-loaded with a separate spring, or arm 112 canbe manufactured from metal or plastic and is spring loaded by live jointaction. Valve 80 is disconnected by raising arm(s) 112 and withdrawingfirst valve component 82 from second valve component 84.

The annular space between outer housing 86 and sleeve 88, as well as theannular space between outer housing 100 and sleeve 102, can be filledwith an absorbent or retention material 118, which can be the samematerial as filler material 90 or 104. Absorbent material 118 can absorband retain fuel that remains in valve 80 when fuel cartridge 16 isdisconnected from fuel cell 18. Alternatively, the absorbent materialcan be placed anywhere that is spaced apart from the fuel flow path.Other suitable absorbent materials include, but are not limited to,hydrophilic fibers, such as those used in infant diapers and swellablegels, such as those used in sanitary napkins or a combination thereof.Additionally, the absorbent materials can contain additive(s) that mixeswith the fuel. Absorbent material 118 can also be used in conjunctionwith valve 10 described above in connection with FIGS. 1-7. For example,housing 20, 32 or 48 is disposed concentrically within an outer housingand the annular space between housing 20, 32 or 48 and this outerhousing is filled with absorbent material 118.

For shipping and storage, a fuel cartridge with valve component 82 or 84can be covered at the opening of the valve component with a cap or afilm, which is removed before the cartridge is connected to the fuelcell.

FIGS. 9( a) and 9(b) show yet another embodiment of the presentinvention. Valve 120 comprises first valve component 122, which issimilar to valve component 12 or 14 described above. Valve component 122has housing 20, 32 and sliding body 22, 34, which is biased againstsealing member 124 by spring 30, 40. Sealing member 124 is pushed bybiased sliding body 22, 34 toward lip 60. Lip 60 is sized anddimensioned to receive pushrod 126. Pushrod 126 defines a channel 128 tocommunicate fuel through the pushrod. Pushrod 126 is the second valvecomponent in this embodiment, and the housing of pushrod 126 is used toopen the internal seal of the first valve component. Channel 128 can beinternal to pushrod 126 as shown. Pushrod 126 may optionally havesealing o-ring 130 adapted to form an inter-component seal with asurface on lip 60. As shown in FIG. 9( b), before the internal seal ofvalve component 122 is opened, pushrod 126 forms an inter-component sealwith sealing member 124. Hence, in this embodiment two inter-componentseals, between lip 60 and o-ring 130 and between pushrod 126 and sealingmember 124, can be formed between the two valve components.

FIG. 10 shows suitable cross-sections for sealing member 124. Theinternal diameter of the sealing member does not need to be constant, sothat pushrod 126 does not need to completely penetrate sealing member124 before a flow path is established, as shown in FIG. 9( b). Sealingmember 124 can also be an o-ring as shown in FIG. 5.

In accordance with an aspect of this embodiment, pushrod 126 can behollow and can have a poppet valve, in the form of biased ball 132,disposed therein. Ball 132 is biased against an inside sealing surfacein the pushrod. Hence, even after the inter-component seal isestablished and the internal seal in valve component 122 is opened, nofuel can flow until biased ball 132 is moved against spring 134 to openflow channel 128. A pump, such as the pumps discussed below, isactivated to pull ball 132 to open the flow path. Spring 134 is sized sothat the seal can be maintained, yet the pump can readily pull ball 132.Alternatively, the poppet valve inside pushrod 126 can be omitted. Thepump can regulate the flow of fuel through the pushrod and can also stopthe flow.

When pushrod 126 is disconnected from valve component 122 and the pumpis turned-off, ball 132 returns to its sealing position. This sealmaintains residual fuel in channel 128 and minimizes the chance of fuelflowing back out of the pushrod, because the seal forms a partial vacuumto keep fuel from flowing even if the pushrod is aligned in the verticaldownward position. This effect is similar to the effect of pinching oneend of a straw to prevent liquid from dripping out of the straw.Additionally, valve component 122 may have filler material 136 locatedbehind the internal seal, as shown in FIGS. 9( a), 9(b), 11(a) and11(b). Alternatively, filler material can be located in front of theinternal seal, e.g., within channel 128 in the same figures. The fillermaterial absorbs fuel and minimizes fuel flow when the valve componentis unintentionally opened. Filler material 136 is usable in all thevalve components disclosed herein, except for the embodiment shown inFIGS. 8( a) and 8(b). In a preferred embodiment, valve component 122 ismated to the cartridge and pushrod 126 is mated to the fuel cell.

Sealing member 124 can also be positioned spaced apart from sliding body22, 34, as illustrated in FIGS. 11( a) and 11(b). In this embodiment,sliding body is interchangeably replaced with ball 50, which is biasedagainst lip 60 to form an internal seal. Sealing member 124 is locatedon the other side of lip 60, and in this embodiment the sealing memberis washer 125 having closed slit 142. Washer 125 forms an optionalsecond internal seal and typically does not allow fuel or other liquidto pass through. Pushrod 126, in this embodiment, has needle nose 144defining channel 128 therein. An inter-component seal is formed betweenneedle nose 144 and washer 125 as the needle nose is inserted throughvalve component 140, and channel 128 is in fluid communication withvalve component 140 after ball 50 is pushed backward. Fuel can flowthrough valve component 140 and pushrod 126 when a pump pulls ball 132against spring 134 to open the internal seal inside pushrod 126.

Sealing member 124 can also be duckbill valve 146 illustrated in FIG.11( c), which is interchangeable with washer 125. Duckbill valve ispositioned between two retainers/lips 148 and has narrowing channel 150,which has an opening adapted to receive pushrod 126. Channel 150 narrowsat sealed end 151, which provides an additional internal seal for valvecomponent 140. An advantage of duckbill valve 146 is that sealed end 151is spaced at a distance “B” from the opening “A,” and opening “A” couldalso be made small, so that it is more difficult for a foreign object,such as a finger of the pulp of the finger, to open the sealunintentionally. Duckbill valve 146 can be used alone or in combinationwith any of the internal seals discussed herein. Preferably, opening “A”is less than about 10 mm and more preferably less than about 5 mm.Preferably, distance “B” is at least about 2 mm and more preferably atleast about 5 mm.

Any of the valve components described herein may also have a leadingmember, such as a long nozzle, to limit access to its internal seal asshown in FIGS. 12( a)-12(c). Valve component 152 has nozzle 154, whichlimits access to an internal seal formed between sliding body 22, 34 andshoulder 156. Preferably, an o-ring or a sealing member is disposedbetween the sliding body and the shoulder, as shown. Nozzle 154 hasopening “A” and length “B,” which limit access to the internal seal.Nozzle 154 is sized and dimensioned to receive pushrod 158, which isadapted to push sliding body 22, 34 to open the internal seal in valvecomponent 152. Pushrod 158 is mounted on valve component 160, which hasan optional internal seal provided by biased ball 132, as discussedabove. Pushrod 158 may have a diameter smaller than the inner diameterof nozzle 154, so that fuel can flow in the annular space between thenozzle and the pushrod, as shown in FIG. 12( b). In this embodiment,pushrod 158 is supported by a plurality of webs 162. Webs 162 definespaces between them, so that fuel can flow pass the webs. Alternatively,pushrod 158 may be hollow and have an outer diameter that issubstantially the same as the inner diameter of nozzle 154, and fuel isselectively flowed through the inside of pushrod 158, as shown in FIG.12( c). In this embodiment, the internal seal provided by biased ball132 helps retain the fuel inside pushrod 158 when valve component 160 isdisconnected from valve component 152 as discussed above. Also, asshown, a pump is provided to pump fuel past biased ball 132. Preferably,opening “A” is less than about 10 mm and more preferably less than about5 mm. Preferably, distance “B” is at least about 2 mm and morepreferably at least about 5 mm.

Access to the valve component may also be limited by another leadingmember, outer sleeve 164, covering valve component 12, 14, as shown inFIG. 13. Opening “A” and length “B” of sleeve 164 are dimensioned torender unintentional opening of the internal seal of the valve componentmore difficult. Sleeve 164 can be made integral to the valve componentor can be connected to the valve component by threads (as shown),adhesive, ultrasonic welding, press-fitting or other means. Preferably,opening “A” is less than 10 mm and more preferably less than 5 mm.Preferably, length “B” is at least 2 mm and more preferably at least 5mm.

In accordance to another aspect of the present invention, duckbill valve146 may have a plurality of wipers 166, as shown in FIGS. 11( c) and 14.Wipers 166 are adapted to form seal(s) with the outside surface ofpushrod 126. As pushrod 126 withdraws from a valve component, e.g.,after a cartridge is filled with fuel or when the cartridge is removedfrom the electronic equipment, pressurized fuel may be present. As thepushrod leaves sealed end 151, pressurized fuel is allowed to expandwithin first chamber 168. As fuel expands, its pressure drops.Additional expansion chambers, such as second chamber 170, can beprovided to drop the pressure of the fluid further. Optionally, as shownin FIG. 14, duckbill valve 146 is provided with material 174 in chamber172 to act on any remaining fuel. Material 174 includes additives thatcan mix with the fuel, filler materials or foams that can absorb andhold the fuel, or swellable materials that absorb and swell to closechannel 150. Preferred absorbent materials include, but are not limitedto, cross-linked polyacrylic acid salts, polyvinyl alcohol,poly(2-hydroxyethyl methacrylate), poly(ethylene oxide),isobutylene-maleic acid copolymers, poly(methacrylic acid) salts,polyacrylaminde, and polyvinylpyrrolidone. These materials are disclosedin the '427 patent application, which has already been incorporatedherein by reference.

The biasing springs disclosed herein are illustrated as helical or coilsprings and rubber springs. However, any type of springs can be used.Suitable springs include, but are not limited to, coil springs, leafsprings, compressed foam springs, and rubber springs, among others.Preferably, the springs are made from materials that are inert to thefuel contained in the cartridge and transported through the valvecomponent to the fuel cell such as Inconel, stainless steel, and rubber.Suitable rubber spring materials include ethylene propylene rubber,ethylene propylene diene methylene terpolymer (EPDM) or Vitron®fluoro-elastomer, Buna N Nitrile, other nitrile rubbers. These materialscan be compressed to provide the biasing force. FIG. 15 showsalternative shapes for the rubber spring. Rubber springs may have ahollow cylindrical shape, as discussed above with respect to FIGS. 7(a)-7(c). Alternatively, instead of having substantially straightsidewalls, the rubber spring may have wavy sidewalls to control thecompression of the spring. The waves control the buckling or compressionof the rubber spring.

For the connecting valves disclosed herein, when the fuel cartridgeneeds to be changed, the inter-component seal is preferably opened afterthe internal seals within the valve components are re-established toisolate the residual fuels within the fuel cartridge. Also, theconnecting valves illustrated in FIGS. 1-3, 6-7, 9 and 11-14 are usablewith pressurized and non-pressurized fuel cartridges.

For use with any of the valves described herein, a pump can be used totransport fuel from the fuel cartridge. Usable pumps can be any pumpcapable of transporting fluid at the desired rate. Preferably, thesepumps are microelectromechanical pumps (MEMS), such as those discussedand claimed in the '793 patent application. The MEMS pump can be eithera field-induced pump or a membrane-displacement pump. A field-inducedpump has an AC or DC electrical field or magnetic field applied to thefuel/liquid to pump the fuel/liquid. Suitable field-induced pumpsinclude, but are not limited to, electrohydrodynamic pump, magnetohydrodynamic pump and electro-osmotic pump. The electrohydrodynamic pumpand an electro-osmotic pump can be used together. Amembrane-displacement pump comprises a membrane and a force is appliedto the membrane causing the membrane to move or vibrate to pump thefuel. Suitable membrane-displacement pumps include, but are not limitedto, electrostatic pump, piezoelectric pump and thermopneumatic pump. TheMEMS pump controls the speed of the flow of fuel and reverses the flow,as well as stopping the flow.

While it is apparent that the illustrative embodiments of the inventiondisclosed herein fulfill the objectives of the present invention, it isappreciated that numerous modifications and other embodiments may bedevised by those skilled in the art. Additionally, feature(s) and/orelement(s) from any embodiment may be used singly or in combination withother embodiment(s). Therefore, it will be understood that the appendedclaims are intended to cover all such modifications and embodiments,which would come within the spirit and scope of the present invention.

We claim:
 1. A fuel cartridge comprising a housing containing a fuel fora fuel cell and a valve component disposed within the housing, whereinthe valve component comprises an first internal seal and an additivethat can mix with a volume of the fuel that is present within the valvecomponent.
 2. The fuel cartridge of claim 1, wherein the valve componentfurther comprises an absorbent material.
 3. The fuel cartridge of claim2, wherein the absorbent material comprises at least one of cross-linkedpolyacrylic acid salts, polyvinyl alcohol, poly(2-hydroxyethylmethacrylate), poly(ethylene oxide), isobutylene-maleic acid copolymers,poly(methacrylic acid) salts, polyacrylaminde, or polyvinylpyrrolidone.4. The fuel cartridge of claim 1, wherein the valve component comprisesa duckbill valve.
 5. The fuel cartridge of claim 4, wherein the duckbillvalve comprises at least one wiper.
 6. The fuel cartridge of claim 1,wherein the internal seal of the valve component can be opened by ahollow tube.
 7. The fuel cartridge of claim 6, wherein the hollow tubeis connected to a second valve component having a second internal seal.8. The fuel cartridge of claim 5, wherein the duckbill valve comprisesone or more chambers formed by the at least one wiper.